1. Field of the Invention
This invention relates to medical instruments, and more particularly to surgical instruments, such as reamers for removing bone or tissue by rotating the instrument back and forth.
2. Description of the Prior Art
A technique developed fairly recently for repairing ruptured vertebrae discs involves a replacement of the disc material with substitute bone material. As part of this technique, it is necessary to remove the disc material carefully between the vertebrae.
Prior instruments for removal of this material were inadequate because they did not permit thorough and efficient removal of the disc material. The space between the vertebrae is small and requires specialized instruments to efficiently and effectively remove the disc material. Prior art instruments were inefficient, and required that the surgery take longer than necessary.
There is a need for an instrument to perform disc removal procedures thoroughly and effectively so that the disc replacement surgery can be conducted safely, efficiently, and effectively.
U.S. Pat. No. 4,660,557, issued to the present inventor, discloses a surgical instrument specially designed for removal of the disc material between the vertebrae. This instrument has proven to be especially effective for disc replacement surgery in the lumbar region. However, the design of this instrument is not effective for surgery in the cervical region, in which the space between the vertebrae is smaller and in which it is more difficult to rotate the instrument in a full circle to remove the disc material.
There is a need for an instrument which can be specially adapted for use in the cervical region for removal of the disc material in disc replacement surgery.